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Panoramic Photography

Panoramic photography is a technique of photography, using specialized equipment or software, that captures images with elongated fields of view. It is sometimes known as wide format photography.his generally means it has an aspect ratio of 2:1 or larger, the image being at least twice as wide as it is high. The resulting images take the form of a wide strip.

 

What equipment do I need?

 

Tripod

Tripod
By using a tripod you can ensure that the camera rotates around a fixed spot and that it stays level. It also makes it much easier to take longer exposures, which may be useful if you want to get a nice sharp picture with everything in focus. You can use a monopod, but you will have to hold it (which means more chance of camera shake and of the position changing between shots. A monopod is useful if there is no space for a tripod, and you can get long poles for shooting panoramas high up (these are in effect monopods) - for examples see AGNOS
Check that you can lock the head of the tripod firmly and that it doesn't wobble when locked. If it does it will be difficult for you to make sure the camera stays level while you are shooting, especially if you have a large camera or if you use a panoramic head , because the weight may make the tripod's head even more unstable.
If you do not use a tripod or fail to keep the photo  camera level, you may have problems stitching your pictures (depends on the software used) and you may end up having to crop your panoramas down, thereby reducing the vertical field of view . This is not true if you shoot a spherical panorama as you can re-align the panorama afterwards in software.

 

Spirit level

A spirit level is a pretty essential extra and you can buy very cheap little spirit levels designed to fit into the hot shoe of an SLR photo camera . Use the spirit level to make sure the tripod's head is level and that when you attach the panoramic head and photo camera, that these are level also.
If you shoot spherical panoramas you do not need to set up the panoramic head to be perfectly level since you can realign the stitched image with the horizon afterwards in software. However a spirit level like this is, in my opinion, nevertheless an essential piece of equipment.

Remote shutter release

If you find that you are doing long exposures quite often, then a remote release cable or an infra red remote release can be useful. By using this you also reduce the likelihood of accidentally knocking the tripod or camera while you are doing the shoot. If you are using a digital SLR photo camera and it has mirror-lockup, using that feature with a remote shutter release allows you to minimise vibrations when you shoot the panorama.


Panoramic head ("pano-head")

Pano-head
A panoramic head is an additional attachment you put on the top of the tripod before you attach the photo camera. It allows you to position the camera so that as you pan to take each picture you are rotating around the no-parallax-point of the photo camera lens. This in turn eliminates parallax which could otherwise prevent you achieving a sharp high-quality panorama. If you look closely at the object movie of the Kaidan Kiwi 900/950 panoramic head you will notice that the centre of the lens is above the point of rotation and that the camera is rotating about a point in the lens, not the photo camera body. For more information see the description of parllax and the article about using a panoramic head.
Panoramic heads also make it easier to rotate the camera smoothly and many have click-stops of some kind and a spirit level. These features are also available in the Q-top, which is a very neat small tripod mount that provides a quick release shoe for the camera. The shoe is held very tightly in position when placed back onto the mount, and the shoe has 30 degree increments to make it easy to shoot a series of pictures for a panorama. But the Q-top is no substitute for a panoramic head.

Wide angle lens

By shooting several pictures and stitching them together, you can create a 360 degree panoramic picture, no matter what lens you have on your camera. A wide angle lens has the advantages that you don't need to take as many pictures and  you can capture more vertically so the picture doesn't look like a narrow 'slit'.If you are considering buying a wide angle lens for your panoramic photography, beware that some stitching software supports only rectilinear ('normal') lenses, some support fisheye lenses and some support both. Be particularly careful to check stitching software if you are intending to use a fisheye lens.If you are new to panoramic photography I suggest you postpone any ideas of buying a special lens until you have shot a few panoramic pictures... you will then have a good idea of whether you want or need a wide angle lens and how wide a lens you need to achieve the sort of pictures you want.An 8mm lens is generally the widest lens available for any camera, and on a full-frame camera will create a circular image that represents approximately 180 degrees in all directions. Unsurprisingly using an 8mm lens or equivalent is the easiest/fastest way to create spherical panoramas in which you can look straight up at the ceiling and straight down at the floor, and not just side to side. If you intend to buy an circular fisheye lens, remember that although there are many products that can stitch these images, not all can. 


Shooting the pictures

 

How many pictures?

Each picture should overlap with the next by up to 50% (or at least somewhere between 30 and 50%). But please note that providing you overlap each picture with the next, it doesn't matter exactly how much overlap you use, and the amount of overlap can be different between each pair of pictures. So, you can just guess 50% overlap and that will be fine. If you think you will need 10 pictures but you take 9 or 11, it doesn't matter!

 

Depth of field

Generally panoramic pictures capture a scene rather than a moment. In other words most panoramic pictures are of places rather than of people or events as such, therefore you will probably want to aim for a crisp picture that captures the entire scene through to the horizon. To do this you want to set a very large depth of field so that everything in shot is in crisp focus, by focusing on the hyperfocal distance.
When determining the depth of field you need, remember that when shooting indoors you do not need to focus further than the walls of the room and therefore you are likely to be able to widen the aperture and consequently reduce the exposure time.
Avoid altering the depth of field because to do this you will need to alter focus, and when you alter focus you subtly change the field of view of your lens. Most software cannot cope with a mixture of lenses being used for a panoramic sequence - they assume the same lens was used throughout, or more specifically that the lens was used with exactly the same settings.


Exposure

That leaves just one thing to play with. Exposure. You might have a scene in which everything is well lit in which case you can probably set an exposure for every frame. However you will quite often come across situations where the lighting changes. Lighting problems can perhaps be generalised as:
  • areas of strong shadow in a scene where there is also strong light
  • light directly at the camera in part of the scene
The first of these is more likely. I find it useful to spin my photo camera around the scene while holding the shutter button halfway . I can then instantly see whether there is going to be a problem because the photo camera will show me in the viewfinder the exposure it thinks is appropriate for each image. If the exposure changes dramatically I will have a problem: if I let the photo camera judge exposure, it will ensure each picture is as good as it can be. But that means any two adjacent images could differ greatly in lighting conditions so that a shadow in one is barely visible in another. That will confuse the stitching application.
I allow the exposure to change by no more than two increments between frames (e.g. if one shot was taken at 1/30sec then the next one should be no less than 1/60sec and no more than 1/15sec). If a scene contains a mixture of brighter areas and darker areas, I will meter correctly for an intermediate position, and then slightly over expose the dark areas (to make them lighter) and slightly under expose the light areas to make them darker




 Panoramic Photo Gallery






 information from panoguide.com

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